CVE-2026-33439

CRITICAL CVSS 4.0: 9.3 EPSS 8.43%
Updated Jul 24, 2026
Openidentityplatform
Parameter Value
CVSS 9.3 (CRITICAL)
Affected Versions before 16.0.6
Fixed In 16.0.6
Type CWE-502 (Deserialization of Untrusted Data)
Vendor Openidentityplatform
Public PoC No

Open Access Management (OpenAM) is an access management solution. Prior to 16.0.6, OpenIdentityPlatform OpenAM is vulnerable to pre-authentication Remote Code Execution (RCE) via unsafe Java deserialization of the jato.clientSession HTTP parameter. This bypasses the WhitelistObjectInputStream mitigation that was applied to the jato.pageSession parameter after CVE-2021-35464.

An unauthenticated attacker can achieve arbitrary command execution on the server by sending a crafted serialized Java object as the jato.clientSession GET/POST parameter to any JATO ViewBean endpoint whose JSP contains <jato:form> tags (e.g., the Password Reset pages). This vulnerability is fixed in 16.0.6.

Attack Parameters

Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
None
No additional conditions
Privileges Required
None
No privileges needed
User Interaction
None
No user interaction needed

Impact Assessment

Confidentiality
High
Complete data leak
Integrity
High
Complete data modification
Availability
High
Complete denial of service

CVSS Vector v4.0

Vulnerable Products 1

Configuration From (including) Up to (excluding)
Openidentityplatform Openam
cpe:2.3:a:openidentityplatform:openam:*:*:*:*:*:*:*:*
— 16.0.6